Intravenous catheter placement unit



`Iuly 26, 1966 w. H. RING ETAL INTRAVENOUS CATHETER PLACEMENT UNIT FiledNov. 6, 1965 INVENTOR A TTORNE YS M Mmef fama? ,6- Ste/6MM United StatesPatent llNTRAi/ENOUS CATHETER PLACEMENT UNl'lf Wallace H. Ring, Karl A.Palmier, Jr., and lames L.

Sorenson, all of Salt Lake City, Utah, assignors to Sorenson ResearchCorp., Salt Lake City, Utah, a corporation'of Utah Filed Nov. 6, 1963,Ser. No. 321,956 Claims. (Cl. 128--Z14) This invention relates toimprovements in a catheter placement unit, and more particularly to sucha unit highly desirable for the placement of an intravenous catheter forparenteral infusions into the body by means of a catheter, although theinvention may have other uses and purposes as will be apparent to oneskilled in the art.

It has now become desirable to place a catheter, particularly one of theintravenous type, by advancing the catheter through a cannulated needleinto a vein or the like while infusion through the catheter takes place.It is also desirable -to avoid the use of stylets or the like to stiifenthe catheter during insertion, with the ultimate danger `of puncturingthe wall of the vein, and also to avoid the use of a split or slottedneedle with the ultimate danger of infection by virtue of anintraluminal plug of tissue forming upon insertion of the needleandultimately contaminating the catheter. The catheter, of course, must bemaintained in a sterile condition at all times and the placement unitmust be such that the catheter can readily, easily, and rapidly beinserted without danger of puncturing a wall of the vein and withoutdanger of contamination. To this end devices have heretofore beendesigned wherein the catheter, usually a exible plastic tube, was guidedby means of a more rigid sheath therearound against bending duringinsertion, the sheath being rupturable and removed after the catheterwas in position and the catheter advancing means associ ated with thehub of the cannulated needle. Some difficulty was experienced, however,with such an apparatus in maintaining a fluid tight disruptable sheathwhich permitted desirably smooth and easy advancement of the catheter;in the removal of the sheath after the catheter has been advanced;insuring that the catheter advancing means would always remain engagedwith the sheath during advancement of the catheter, and then easily andfirmly engaging the catheter advancement means with the needle hub.

With the foregoing in mind, it is an important object of this inventionto provide a catheter placement unit embodying a plastic sheath morerigid than the catheter contained therein and which is easily lengthwisedisrupted by the catheter advancing means, by virtue of the fact thatthe sheath while having a longitudinal slit is not physically sealed butthe slit remains closed by virtue of the inherent resiliency in thesheath itself.

Another object of the instant invention is the provision of a catheterplacement unit in which a plastic sheath protects the catheter beforeand during advancement thereof, the sheath being secured to the hub of acannulated needle, and the structure being such that the sheath isautomatically released from the needle hub when the catheter is fullyadvanced.

It is also a desideratum of this invention to provide a catheterplacement unit embodying a protective sheath containing a catheter andmeans for advancing the catheter which actually embrace the protectivesheath, whereby the catheter advancing means and sheath cannot becomedisengaged from each other until the sheath is removed after advancementof the catheter.

A further feature of this invention is the provision of a catheterplacement unit embodying a cannulated needle, a protective sheath with acatheter therein, and means .3,262,443 Patented July 26, 1966 "ice thecatheter advancing means firmly engage the hub o f the needle when thecatheter has been fully advanced.

It is also an object of this invention to provide a catheter placementunit embodying the aforesaid desiderata and objects, yet which issufficiently economical to warrant only a single usage after which theentire unit may be discarded.

While some of the more salient features, characteristics and advantagesof the instant invention have been above pointed out, others will becomeapparent from the following disclosures, taken in conjunction with the lacompanying drawing, in which:

for advancing the catheter, the structure being such that FIGURE 1 is afragmentary side elevational view of a catheter placement unit embodyingprinciples of the instant invention connected to a part of an infusionsystem;

FIGURE 2 is an enlarged end view taken from the right-hand side ofFIGURE 1, illustrating the infusion system tube in section;

FIGURE 3 is an enlarged fragmentary central vertical sectional viewtaken substantially as indicated by the line III-III of FIGURE 2,looking in the direction of the arrows and showing parts in elevation;

FIGURE 4 is a fragmentary sectional view similar in character andlocation to FIGURE 3 but showing the catheter fully advanced; and

FIGURE 5 is a fragmentary vertical sectional view taken substantially asindicated by the line V-V of FIGURE 4.

A-s shown on the drawings:

All parts of the instant invention may satisfactorily be made of asuitable plastic material, preferably transparent, with the soleexception of the cannulated needle itself, which is preferably metal.

The illustrated embodiment of the instant invention embodies a hollow orcannulated needle l. having a relatively narrow annular flange 2 on the4outer end thereof. Around the outer end portion of the needle is atubular bushing 3 which is secured tightly to the needle. This bushinghas an enlarged outer end or annular flange #i and in that portion ofthe bushing the enlarged end 2 of the needle is firmly embedded. Theenlarged end l of the bushing provides an inner shoulder S, as seen inFIG- URE 4. The needle is also provided with a hollow hub 6, by'means ofwhich it may be manipulated for a venipuncture or the like, and this hubis rmly seated. on the inner part of the bushing 3. The bushing 3 andthe hub 6 may be cemented or equivalently secured together so as to formsubstantially an integral structure with the needle.

The outer part of Ithe hub is enlarged to provide an annular space 7therein between the hub and the bushing 3. Within that space '7 is aslidable sleeve 3 having an inner annular ange 9 on its inner end whichabuts the aforesaid shoulder 5 on the bushing when the device isinitially made and prior'to use, as seen in FIGURE 3. A Itubularcatheter sheath lltl has one end fr-ictionally engaged Within the sleeve8. This engagement is relatively lirm to maintain the parts united untilafter advancement of the catheter, but a sheath and sleeve may bequickly disengaged at the completion of an operation.

The sheath lll is preferably made of a non-wettable plastic material andis provided with ya slit 1l extending longitudinally thereof along thetop of the unit. The sheath is preferably extruded, polyethylene beingone satisfactory material, in such a manner that it has an inherentresiliency which .acts to maintain the-slit l1 closed at all times,there 4being no-physical seal added to maintain the sides of the slit incontact. Thus, we have provided what might well be termed asurface-tension seal, because the plastic not being wettable,surface-tension of any liquid, outside or within the sheath, preventsthat liquid from flowing through the relatively rmly closed slit 11. Theclosure of the slit 11, however, is amply sufficient to maintain thecontents of the sheath in a sterile condition. The outer open end of thesheath may be closed prior to usage by a friction fitted cap 12 or in anequivalent manner to preserve sterility.

Inside the sheath is a catheter 13, preferably a slender flexible tubeof plastic material, less rigid than the sheath 10. As seen in FIGURE 3,the catheter extends well into the needle 1 but does not project fromthe sharp end thereof. The outer end of the catheter 13 is locked,

cementitiously or equivalently, in a hub-like actuator or catheteradvancing means generally indicated by numeral 14. This actuator 14 ispreferably made in two separate parts for purposes of economy sincerelatively simple two-piece molds may be utilized.

The lower part of the actuator L14 comprises a tubular member 15 throughwhich the sheath 10 extends, the tubular portion 15 being of suflicientdiameter to receive the sheath cap 12, as clearly seen in FIGURE 3l Theother end ofthe tubular member 15 is reduced in diameter as indicated at16 to rather intimately fit the sheath 10 and slide thereover duringadvancement of the catheter. Upstanding from the tube 15 on the upperside thereof is a disc-like cover 17 from the outer side of whichextends a triangular projection 18 of a width approximating the diameterof the catheter.

The other part of the actuator 14 comprises a tubular member 19, havinga slot therein to accommodate the aforesaid projection 18, and the innerend of which is closed by the cap 17. This member 19 has an upperpassage to accommodate -the outer end of the catheter and a reducedouter end portion 20 shaped in the manner of a Leur fitting to receivethe end of an infusion tube 21 connected to any suitable infusionapparatus. Depending from the member 19 is a blunt edged tongue orprojection 22 which extends through a suitable slot in the tubularmember 15, down inside the sheath 10 through the slit 11. Thisprojection 22 complements the laforesaid projection 1S in forming anupwardly sloping track for the catheter. The projection 22', as bestseen in FIGURE 5, is preferably slightly wider than the catheter so thatit establishes a somewhat oval-shaped opening 23 at the slit in thesheath. With the slit closed in the manner above explained, it is notnecessary to utilize `a knife edge projection to separate the walls oneach side of the slit, but the [blunt ended projection 22 is quitesatisfactory for that purpose. As seen `best in FIGURE 5, the cathetereX- tends upwardly near the center of the oval opening 23 and thereforeis not injured by sliding along against the walls defining the slit 11,because as the actuator is moved along the sheath 10 the oval shapedopening in the sheath will travel along with the projection 22.

The two tubular members 15 and 19 are cemented together at points ofcontact including the cover disc 17 securely so as to form, in effect,an integral structure.

In use, the instant invention is extremely simple and effective. It willbe understood, of course, as is well known in this art, that a suitablecap will be disposed over the needle 1 to maintain sterility, andlikewise a disposable cap will be placed over the portion 20 of theactuator, and this is removed as well as the needle cap at the start ofthe operation. First, the device may be connected to the infusion tube21, and the catheter and needle flushed out to remove any air andsterilization residue that may in the system. Then, the hub of theneedle may be grasped by the hand of the operator and the Veni-puncturemade. While infusion continues, the actuator 14 is pushed along thesheath 10 the slit 11 opening in front of the projection 22 and closingbehind it as the actuator advances. The catheter moves along ahead ofthe actuator, being prevented from bending lby the sheath 10, passingout through the point of the needle into the vein. The catheter may thusbe easily and rapidly advanced into the desired position without the useof a split needle or any form of stylet and with substantially no dangerof injuring the wall of the vein.

When the catheter is almost fully advanced, and the parts approach theposition seen in FIGURE 4, it will be noted that the reduced end portion16 will contact the sleeve 8 in the needle hub, and force this sleeveinwardly from the position seen in FIGURE 3 Ito the position seen inFIGURE 4, thereby disengaging the sleeve from the end of the sheath 10.As seen in FIGURE 4, when the catheter is fully advanced, the reducedportion 16 of the tube 15 seats firmly within the hub 6 of the needleagainst the end of the sleeve 8, and the sheath may be easily withdrawnthrough the actuator and discarded.

It will be noted that during the placement of the catheter, thesurface-tension seal of the slit in the sheath permits smooth even `andrelatively rapid advancement of the actuator, and the actuator mustremain in proper engagement with the sheath at all times until thesheath is discarded. When the reduced end portion 16 of the actuator isengaged with the needle hub, the sheath may be easily withdrawntherefrom, without the danger of any jerky action that might causeinjury by the needle. After placement of the catheter, the needle may bewithdrawn from the body of the patient, leaving the major portion of thecatheter in proper position within a vein or other opening, and thecatheter taped to the patients skin in a well known manner.

The cap 12 on .the outer end of the sheath may be removed :at the startof the operation if so desired to permit ready expulsion tof air throughthat end, and air might escape through the opening 23 in the slit of thesheath, so that there is no danger of any air being forcedintravenously. The sheath will only occasionally acquire a quantity ofblood from leakage between ythe catheter and the needle, and since thesurface of the tube is nonwettable the blood is prevented from flowingmore than an inch or two into the sheath. When the sheath is removed,the blood remains within it and is discarded along with the sheath.There is no objectionable mess, and the entire operation may be donesmoothly without spilling any blood on the outside.

From the foregoing, itis apparent that We have provided a highlyefficient form of catheter placement unit, suiciently economical for asingle usage, and which `may be manipulated with complete sterility ofthe catheter in a smooth and facile manner with no danger to the patientand with no mess occurring when the catheter is placed.

It will be understood that modifications and variations may be effectedwithout departing from the scope of the novel concepts of lthe presentlinvention.

We claim as our invention:

1. In a catheter placement unit,

a cannulated needle,

hollow hub means on said needle,

a sleeve slidable in said hub means,

a catheter sheath having one end frictionally engaged in said sleeve,

said sheath having a slit therein extending longitudinally thereof,

a catheter in said sheath with one end extending into said needle,catheter advancing means associated with said sheath and connected withthe other `end of the cat-heter,

means on said advancing means to open the slit in said sheath as theadvancing means are moved therealon g, and

an end portion on said advancing means of a size to push said sleeve outof engagement with said sheath and seat in the hub means of said needlewhen the catheter is fully advanced.

2. In a catheter placement unit,

a cannulated needle,

hollow hub means on said needle,

a sleeve slidable in said hub means,

`a catheter sheath having a longitudinal slit therein and one endfrictionally engaged by said sleeve,

a catheter in said sheath with one end extending into said needle, and

cat-heter advancing means movable along said sheath to advance thecatheter through said needle while spreading said sheath at said slit,and

means on said advancing means to slide said sleeve off the end of saidsheath and seat in said hub means when the catheter is advanced.

3. In a catheter placement unit,

a cannulated needle,

a hollow hub on said needle,

a catheter sheath engaged with said needle hub,

said sheath having a longitudinal slit therein and possessing aninherent resiliency tending to maintain said slit closed,

la catheter in said sheath with one end extending into said needle,

catheter advancing means securely connected to the other end of saidcatheter `and having a portion embracing said sheath land slidabletherealon-g, and

means on said advancing means to spread said sheath at said slit as thecatheter is advanced through said needle.

4. In a catheter placement unit,

a cannulated needle,

a hollow hub on said needle,

movable means in said hub,

Ia catheter sheath frictionally connected at one end to said movablemeans,

said sheath having a longitudinal slit therealong closed by the inherentresiliency of said sheath,

a catheter in said sheath with one end extending into said needle andthe other end portion extending through said slit,

a catheter actuator slidable along said sheath and,

secured to the extending end portion of the catheter,

a blunt projection on said actuator extending into said sheath behindythe catheter and opening said slit wider than the catheter, and

an end portion `on said actwator sized to enter the needle hub anddisengage said movable means from. said sheath when the catheter isadvanced.

5. In a catheter placement unit,

a cannulated needle,

hollow hub means on said needle,

movable means in said hub,

a catheter sheath having one end removably connected to said movablemeans,

a catheter in said sheath with one end extending into said needle,

means to advance said catheter through said needle, and

means on said advancing means to release the engagement of sa-id movablemeans and said sheath when the catheter is advanced to penmit removal ofsaid sheath.

References Cited by the Examiner UNITED STATES PATENTS 5/1965 Ring12S-214 ROBERT E. MORGAN, Primary Examiner.

DALTON L. TRULUCK, Examiner.

1. IN A CATHETHER PLACEMENT UNIT, A CANNULATED NEEDLE, HOLLOW HUB MEANSON SAID NEEDLE, A SLEEVE SLIDABLE IN SAID HUB MEANS, A CATHETER SHEATHHAVING ONE END FRICTIONALLY ENGAGED IN SAID SLEEVE, SAID SHEATH HAVING ASLIT THEREIN EXTENDING LONGITUDINALLY THEREOF, A CATHETER IN SAID SHEATHWITH ONE END EXTENDING INTO SAID NEEDLE, CATHETER ADVANCING MEANSASSOCIATED WITH SAID SHEATH AND CONNECTED WITH THE OTHER END OF THECATHETER, MEANS ON SAID ADVANCING MEANS TO OPEN THE SLIT IN SAID SHEATHAS THE ADVANCING MEANS ARE MOVED THEREALONG AND AN END PORTION ON SAIDADVANCING MEANS OF A SIZE TO PUSH SAID SLEEVE OUT OF ENGAGEMENT WITHSAID SHEATH AND SEAT IN THE HUB MEANS OF SAID NEEDLE WHEN THE CATHETERIS FULLY ADVANCED.